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In this paper, we propose a novel contour search algorithm (CSA) for image processing. Its efficacy is evaluated through a comparative analysis with established techniques such as Canny Edge and Snakes: Active contour models, utilizing infrared thermography (IRT) images. Based on the new CSA, we investigate the influence of different pulse shapes on the IRT post-processing methodology, particularly focusing on the thermal shock response spectrum (TSRS), using two different heat sources: xenon flash lamps and a laser. Moreover, this allows for a more precise quantitative comparison of the TSRS with existing IRT post-processing techniques, including pulse phase thermography and thermal signal reconstruction, concerning the detection of defects in composite materials, particularly in carbon fiber-reinforced polymer. A quantitative comparison was performed using the Tanimoto criterion and signal-to-noise ratio. A more detailed analysis is conducted to identify inherent limitations and potential benefits of the new TSRS methodology. We further investigate and experimentally confirm our previous finding on the qualitative correlation between the one-dimensional thermal N-layer model and test data from the TSRS optimization process for defect determination. This correlation can eliminate the time-consuming optimization step, making TSRS a more attractive alternative to common IRT methods and enhancing the quantitative description of defects. [ABSTRACT FROM AUTHOR]

The key challenge of producing titanium-aluminum alloy by vacuum induction melting technology is to develop crucible materials with excellent thermal stability and thermal shock resistance. In this work, Ba 0.8 Ca 0.2 ZrO 3 ceramic materials were synthesized by pressure-less sintering of BaZrO 3 and CaZrO 3. In order to improve the thermal shock resistance of Ba 0.8 Ca 0.2 ZrO 3 , a pore-forming agent of BaCO 3 was introduced into the material. The thermal shock resistance of the material improved significantly and reached its maximum when 9 wt% BaCO 3 was added (the retained flexural strength increased from 2.61 MPa to 3.52 MPa). At the same time, the addition of BaCO 3 significantly reduced the penetration of the crucible material by the melt and the pollution of the secondary-phase alloy in the material (the penetration depth decreased from ∼200 μm to ∼100 μm). Based on the combination effect of Ba 0.8 Ca 0.2 ZrO 3 solid solution and fine closed pores, a potential titanium-aluminum alloy smelting material with excellent chemical stability and thermal shock resistance was obtained. [ABSTRACT FROM AUTHOR]

To develop a high-temperature-resistant adhesive specifically for quartz glass, several groups of aluminum phosphate-based adhesives with different P/Al ratios and Si/B 4 C ratios were prepared, and the bonding performance and mechanism were systematically analyzed. Adding Si and B 4 C affected the decomposition process of phosphates, mainly in terms of the types of decomposition products and the crystal transformation of phosphates. Their addition avoided the generation of metaphosphate and improved the component stability of the adhesive matrix. The oxidation of Si and B 4 C brought about considerable quality compensation, which was crucial for maintaining the structural integrity of the adhesive layer. Besides, the oxidation products further reacted with the adhesive and quartz substrate to form ceramic or glass phases, significantly improving the bonding performance. When the P/Al ratio and Si/B 4 C ratio were 2:3 and 10:3, APSB adhesive presented the best performance. After curing at room temperature or pre-treatment at 1200 °C, the bonding strength reached 16.3 MPa and 14.6 MPa, respectively. After pre-treatment at 1200 °C, APSB could provide above 6 MPa in extreme environments with the range of RT∼1200 °C. The thermal shock resistance of APSB was superior to its thermal cycling resistance. After 10 thermal shocks at 600 °C, 800 °C, and 1000 °C, the bonding strength of APSB is 4.52 MPa, 4.33 MPa, and 7.33 MPa, respectively. Nevertheless, the CTE of APSB adhesive after sintering remained stable at 5.4 × 10−6 K−1, which was still significantly different from the CTE (0.5 × 10−6 K−1) of quartz glass. Therefore, there is great potential for developing low-expansion adhesives in the near future. [ABSTRACT FROM AUTHOR]

Y 2 O 3 ceramics are increasingly recognized for their excellent vacuum stability and high-temperature chemical stability in the field of functional materials research. However, their poor thermal shock resistance renders them susceptible to spalling and damage during use, thus restricting further applications. To address this issue, the low thermal expansion coefficients of Y 2 SiO 5 materials were leveraged. Through an in situ reaction between SiO 2 and Y 2 O 3 , a Y 2 SiO 5 phase was generated that induced a thermal expansion mismatch with Y 2 O 3 , thereby enhancing the thermal shock resistance of the ceramic. Using Y 2 O 3 fine powder as the primary material, silica sol and nano-SiO 2 were selected as reactive silicon sources to prepare Y 2 O 3 –Y 2 SiO 5 composite ceramics at 1750 °C. The impact of the different silicon sources and Y 2 SiO 5 phase content on the microstructure, mechanical, and thermal properties of the composite ceramics was studied. The results demonstrated that the in situ formation of Y 2 SiO 5 significantly improved the thermal shock resistance of the composite ceramic. Specifically, increasing the SiO 2 content led to a gradual rise in the volume fraction of Y 2 SiO 5 formed between Y 2 O 3 grains, thereby increasing the residual flexural strength and enhancing the hardness and elastic modulus. The low thermal expansion coefficient of Y 2 SiO 5 reduced the overall thermal expansion coefficient of the composite material, thereby improving the thermal shock resistance. Moreover, the thermal expansion coefficient mismatch between the Y 2 O 3 and Y 2 SiO 5 phases induced numerous microcracks within the material, providing thermal stress relief within the microcracks and markedly improving the resistance of the ceramic to thermal shock. [ABSTRACT FROM AUTHOR]

MgO-SiC-C refractories demonstrate distinguished thermal shock resistance and slag resistance, making them a promising alternative to magnesia-chrome refractories in matte smelting furnaces. Herein, we propose a novel approach to enhance both oxidation resistance and slag penetration resistance of such refractories by incorporating Si 3 N 4 -Fe powder. The results demonstrated that adding Si 3 N 4 -Fe powder effectively enhanced their overall performance. The oxidation resistance of the specimen with 6 wt% Si 3 N 4 -Fe was greatly improved because Si 3 N 4 in Si 3 N 4 -Fe could promote in-situ reactions to form more forsterite, and the FeO formed by iron oxidation could react with SiC to form Fe-Si alloys; the formed forsterite and Fe-Si alloys worked together to prevent oxygen intrusion. Meanwhile, Si 3 N 4 in Si 3 N 4 -Fe promoted the formation of forsterite layer in the corrosion area of refractories, and the reaction of Si 3 N 4 and Fe in Si 3 N 4 -Fe formed Fe-Si alloys to prevent slag penetration, which greatly improved the resistance to matte slag penetration of the refractories. [ABSTRACT FROM AUTHOR]

Aiming to further improve the properties of novel MgAl 2 O 4 -Si 3 N 4 ceramic used as solar thermal absorbing material in concentrating solar power, effects of Sm 2 O 3 and TiO 2 on performance of the composites were investigated especially the mechanisms of different additives on microstructure and high temperature stability. The results show that both additives can accelerate sintering, reduce sintering temperature, improve the density and high temperature stability via liquid phase sintering mechanism. Besides, TiO 2 can form displacement solid solution with Al 2 O 3 to promote the sintering process. Sm 2 O 3 is more conducive to improving the bending strength due to its function of increasing the length diameter ratio of β-Si 3 N 4. TiO 2 is more favorable for improving solar absorption owing to the distinctive absorption spectrum and large number of cation vacancy caused by substitution of Al3+ by Ti4+. MgAl 2 O 4 -Si 3 N 4 composites with Sm 2 O 3 and TiO 2 additives have better performance than MgAl 2 O 4 -Si 3 N 4 , Si 3 N 4 and SiC ceramics prepared via the same procedure, which makes it a certain choice for solar thermal absorbing material. [ABSTRACT FROM AUTHOR]

As the most prospective media material for porous media burners, silicon carbide reticulated porous ceramic (SiC RPC) is required to possess a high porosity to fulfill efficient combustion, as well as exceptional thermal shock resistance to withstand the thermal stress generated during the start-up and shutdown processes. To achieve the strengthening and toughening of highly porous SiC RPC, three-layered struts were constructed, and in-situ whiskers were formed in SiC RPC through vacuum infiltration and sintering under a nitrogen atmosphere in this work. The results indicated that the three-layered struts were formed after the preform was conducted with vacuum infiltration, encompassing a mullite coating, a silicon carbide layer and a mullite inner layer. When Si powder and flake graphite were incorporated into the SiC slurry, numerous SiC whiskers were formed in situ within the SiC skeleton. The formation of SiC whiskers was attributed to the enhancement of SiC RPC, resulting in an increase in CCS from 0.22 MPa to 0.55 MPa. Additionally, the residual strength retention rate after water quenching at 1100 °C was elevated from 41.6 % to 70.2 %. Moreover, the SiC RPC containing SiC whiskers exhibited an impressively high porosity of 83 %, leading to a surface temperature of 688 °C and a heating efficiency of 16.4 °C/min during the combustion process. [ABSTRACT FROM AUTHOR]

The hydrated magnesium carboxylate cement (HMC) with varying C 6 H 5 O 7 2−/Mg2+ ratios was prepared by adjusting the ratio of citric acid to magnesia in this study, and its effect on the performances of corundum-spinel refractory castables were investigated. The results revealed that the HMC bonded castable's workability was improved by increasing the C₆H₅O₇³⁻/Mg2⁺ ratio. Specifically, the sample C-EX (citric acid/magnesia = 4.5) compared to the standard sample NO (citric acid/magnesia = 3.5), the setting time was extended by 100 min, and the flow value increased by 77.6 %. Hydration kinetics experiments demonstrate that this phenomenon was due to the excess citric acid inhibiting HMC ionization. Furthermore, increasing the C₆H₅O₇³⁻/Mg2⁺ ratio also enhanced castables' medium-temperature mechanical properties and thermal shock resistance. The excess citric acid enhanced the castable slurry's performance, resulting in a 37.8 % increase in cold modulus of rupture for the C-EX sample after sintering at 500 °C compared to the sample NO. The fracture strength after thermal shock is 27.9 % higher in sample C-EX than in sample NO. This improvement is attributed to the 82.1 % increase in toughness of the sample C-EX, which facilitates the micro-cracks formation but inhibits their propagation. However, it should be noted that increasing the proportion of citric acid reduced the aspect ratio of HMC hydration products, leading to decreased mechanical properties of the castables. [ABSTRACT FROM AUTHOR]

Coal gangues i a solid waste during the coal mining process and the accumulation of coal gangue will harm the environment. Therefore, solid waste utilization of coal gangue is required to reduce the environmental damage. In this paper, cordierite ceramics are successfully prepared via a solid‐phase sintering using coal gangue, Al2O3, and MgO as raw materials. The effects of sintering temperatures on the microstructures, phase stability, and thermal properties of ceramics are investigated. The results show that the properties of cordierites prepared at 1200°C are close to those of prepared by the traditional method, and the synthesized ceramics have thermal expansion coefficients (TECs) and conductivity of 4.1–10−6 K−1 and 1.72 W·m−1 K−1 at 900°C, respectively. The sample prepared at 1200°C has good wear resistance (η) with a wear resistance coefficient of 0.507, and an excellent thermal shock resistance, which can withstand 15 times of cold and hot shocks at 1100°C without any cracks on the surface. This study systematically elucidates the thermal/mechanical properties of the synthesized cordierite, and the feasibility of using coal gangue as raw materials prepared cordierite ceramics as refractory materials. This work presents an effective solution to mitigate the challenge of coal gangue disposal. [ABSTRACT FROM AUTHOR]

Porosity is a critical microstructural factor in ceramic materials, influencing their mechanical and thermal properties. However, the detailed mechanisms through which porosity, grain size, and grain boundary fracture energy affect the thermal shock resistance of porous ceramics are still not fully understood. This study introduces a dual‐scale model that integrates these microstructural parameters to predict fracture toughness and thermal shock resistance. Using the single‐edge V‐notch fracture toughness testing principle, we calculate the thermal stress intensity factor and establish its relationship with temperature differentials. The critical temperature differential, which marks the onset of thermal shock damage, is determined when the thermal stress intensity factor reaches the fracture toughness threshold. The model reveals a significant interplay between porosity, grain size, and grain boundary fracture energy, with fine‐grained ceramics (grain size < 10 µm) showing a sharp decrease in fracture toughness as porosity increases, while coarser‐grained ceramics are less affected by porosity. These findings provide a deeper understanding of the microstructural optimization needed to enhance the thermal shock resistance of high‐performance porous ceramics. [ABSTRACT FROM AUTHOR]

Because of the fatigue resistance and light weight, carbon fiber reinforced resin composite (CFRP) has widely used in expanded solar panels, key components of space stations and antenna panels. However, the space environment of solar irradiation will cause the CFRP temperature rise due to its high solar absorption, which affects the long-term application. It is necessary to prepare thermal control coating (TCC) on the surface of CFRP. In this paper, a new preparation method of CFRP surface coating by gravity deposition is reported to obtain ZrO 2 and polytetrafluoroethylene particle stacking structure with low solar absorption. The high scattering intensity of particle stacking structure coating was verified by simulation. Through the analysis of the morphologies and XPS of the coating, the optimal ZrO 2 content was determined, and the particle stacking structure was proved. The coating exhibits good thermal shock property. The solar absorption of the coating is as low as 0.08, with a surface density of 196 g/m2, and the surface temperature can be reduced by 38.8 °C under irradiation, which provides a new prospect for the application of thermal control coating on the CFRP. [ABSTRACT FROM AUTHOR]

The sagger, primarily composed of aluminum-silicon, serves as an essential vessel in the sintering process of ternary lithium battery anode materials (LiNi x Co y Mn 1-x-y O 2 , LNCM). However, the acidic oxide SiO 2 in the sagger material readily reacts with Li 2 O in the cathode material, forming substances such as LiAlO 2 or LiAlSiO 4 , resulting in volume expansion, which makes the sagger spalled and damaged. In this study, β-Al 2 O 3 –MgAl 2 O 4 multiphase materials with excellent alkali resistance were prepared using the high-temperature solid-state method. The effects of anhydrous sodium carbonate content and heat treatment temperature on the properties of the composites were investigated, and the thermal shock resistance of the specimens was evaluated by the water-rapid-cooling method, as well as the LNCM corrosion resistance of the specimens was evaluated by the static crucible method. The results showed that the overall performance of the specimens was the best at a anhydrous sodium carbonate content of 6 wt%, with a compressive strength of 57.50 MPa and a flexural strength of 42.49 MPa after firing at 1600 °C for 4 h. The strength retention of the specimens was 33.21 % after one thermal shock at a thermal shock temperature of 900 °C. The specimens showed excellent resistance to erosion as there were no obvious erosion traces on the surface of the specimens after undergoing five cycles of erosion. [ABSTRACT FROM AUTHOR]

Alumina-spinel and alumina-magnesia castables are important for steel ladle applications primarily for the bottom and side wall areas respectively. Presence of spinel in alumina castables enhances the resistances against corrosion and thermal shock and improves the performance and service life of the steel ladles. Development of these type of castables is planned in the present study in presence of Cr 2 O 3 as an additive using high alumina cement as binder. Variation in spinel (10 and 20 wt%) and MgO (2.8 and 5.6 wt%) content was also explored, along with two different particle size distributions (q value 0.21 and 0.29) for different flow consistencies. The castable compositions were processed conventionally and evaluated for various refractory properties after heat treatments at 110, 1000 and 1550 °C. Both the castables showed well developed refractory properties with alumina-magnesia castable having better slag resistance due to greater extent of calcium hexa aluminate phase formation protecting the refractory. [ABSTRACT FROM AUTHOR]

A self-built automatic platform was built to evaluate the thermal shock performances of Cansas-III SiC fibers at 1200 °C in air up to 500 cycles, the corresponding oxidation and damage mechanisms were then revealed. The results showed that oxide scale was formed during thermal shock with a thickness of about 1 μm, the core was not oxidized via its protection. The fiber roughness increased before 100 cycles due to the decomposition of the amorphous SiC x O y phase, and then decreased as the formation of oxide scale. Within Cansas-III SiC fibers, structural defects of free carbon increased as the increasing I D /I G values, in addition, the TO peak shifted to the left, which both demonstrated that the relative movements occurred among SiC grains and residual stresses were then emerged. To clarify the axis and radial cracking of the oxide scale, a modified formulation considering nonzero shear strain components was then proposed to calculate the related residual stresses. The peeling and cracking of the oxide scale was ascribed to the residual stresses of GPa level among SiC grains and the thermal expansion mismatch between the oxide scale and the core. [ABSTRACT FROM AUTHOR]

In this study, corundum-magnesium aluminate spinel (C-MAS) composite heat storage ceramics were synthesized by co-adding MgO and TiO 2 to Al 2 O 3. The effects of TiO 2 and the Al 2 O 3 /MgO ratio on the heat storage performance were evaluated. The findings reveal that Ti4+ integrates into the corundum and MAS lattice, leading to lattice distortion and facilitating solid-phase reaction and MAS generation. Optimal performance is observed at an Al 2 O 3 /MgO ratio of 95:5, with dense structure, minimal pores, and uniform grain size, exhibiting exceptional thermal shock resistance. They withstand 30 thermal shocks (RT-1100 °C) with a 7.12 % increase in bending strength. Moreover, the addition of MgO and TiO 2 significantly enhances the specific heat capacity, characterized by an average specific heat capacity of 1.06 J·g−1·°C−1 and a heat storage density of 1443.83 kJ·kg−1 (RT-1100 °C). TiO₂ introduces additional point defects or alters existing ones in the Al₂O₃ matrix, increasing heat capacity through defect thermal motion. The formation of MAS leads to higher specific heat capacity, due to the greater degrees of freedom and complex lattice vibrations of the spinel structure. These properties position C-MAS composite ceramics as promising candidates for the heat storage materials of the new generation of solar thermal power generation. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of layer gradient thermal protection coatings based on NiCrAlY and YSZ obtained by detonation spraying. Modern gas turbines and high-temperature units operate under extreme temperatures and aggressive environments, which requires effective protection of components from wear, corrosion, and thermal shocks. In this study, the use of layer gradient coatings consisting of alternating layers of NiCrAlY and YSZ was investigated with the aim of solving the problem of thermal stress accumulation due to a smooth change in the composition of the layers. Microstructural and phase analysis showed that alternating layers of NiCrAlY and YSZ formed a dense layer gradient structure with clear interphase boundaries and low porosity. Detonation spraying led to a complete transformation of the monoclinic ZrO2 phase into a tetragonal one, which significantly increased the mechanical strength of the coating and its resistance to thermal shocks. Sample 1D1 demonstrated excellent tribological and corrosion properties in a 3.5% NaCl solution, which can be explained by its higher density and reduced number of pores. Mechanical tests revealed stable values of hardness and wear resistance of the coating, especially for the 1D1 coating. Studies have shown that coatings are resistant to thermal shocks, but thicker layers show a tendency to peel off after thermal cycling. The obtained results indicate high prospects for the use of layer gradient coatings based on NiCrAlY and YSZ for the protection of gas turbine components and other high-temperature installations operating under extreme loads and aggressive environments. [ABSTRACT FROM AUTHOR]

A novel TiB2-CeO2-modified (Nb,Mo,Cr,W)Si2 coating was prepared on a Nb-5W-2Mo-1Zr alloy substrate using two-step slurry sintering and halide-activated pack cementation to address the limitations of a single NbSi2 coating in meeting the service requirements of niobium alloys at elevated temperatures. At 1700 °C, the static oxidation life of the coating exceeded 20 h, thus indicating excellent high-temperature oxidation resistance. This was due to the formation of a TiO2-SiO2-Cr2O3 composite oxide film on the coating surface, which, due to low oxygen permeability, effectively prevented the inward infiltration of oxygen. Additionally, the dense structure of the composite coating further enhanced this protective effect. The composite coating was able to withstand over 1600 thermal shock cycles from room temperature to 1700 °C, and its excellent thermal shock performance could be attributed to the formation of MoSi2, CrSi2, and WSi2 from elements such as Mo, Cr, and W, which were added during modification. In addition to adjusting the difference in thermal expansion coefficients between the layers of composite coatings to reduce the thermal stress generated by thermal shock cycles, the formation of silicide compounds also improved the overall fracture toughness of the coating and thereby improved its thermal shock resistance. [ABSTRACT FROM AUTHOR]

Depositing a tritium permeation barrier on the surface of materials is a key method for reducing tritium permeability. During actual operational processes, the surface of the tritium permeation barrier may experience mechanical damage, such as spalling and scratches. The hydrogen permeability resistance of the coating will degrade due to such forms of mechanical damage. It is a significant engineering challenge to evaluate the impact of these damages on the coating's tritium resistance. In this experiment, the mechanical damage to the FeAl/Al2O3 tritium permeation barrier on 316L stainless steel was simulated through scratching, debonding, and thermal shock. Subsequently, a hydrogen isotope gas drive permeation (GDP) test was conducted. The influence of the degree of mechanical damage on the coating's tritium permeation behavior was assessed and discussed. The results indicate that, under the same damage mechanism, the coating's tritium permeability resistance is positively correlated with the integrity of the coating. Additionally, the impact of scratches on the coating surface is more severe than that of other damage mechanisms. [ABSTRACT FROM AUTHOR]

Concrete is the most extensively used construction material in the world due to its widespread availability and ease of placement. However, the hydration process after concrete placement generates a significant amount of heat. For beams, columns, and slabs that have a large surface area-to-volume ratio, this heat dissipates easily through the surface. However, for dams, raft foundations, and bridge abutments, heat dissipation is slow due to the small surface area-to-volume ratio. Such units are identified as 'Mass concrete' and require special consideration for managing this heat generation and thermal behaviour to avoid thermal cracking. This article presents a case study where cracking was observed during the construction of a highway bridge abutment in Oman. The study discusses forensic measurements and uses numerical modelling to investigate and identify the cause of cracking. The numerical model used showed good agreement with the field measurements and revealed that the cracking occurred due to a thermal shock caused by the early exposure of the mass concrete surface to low ambient temperature. The study also proposes measures to control and minimise thermal cracking in arid regions like Oman. [ABSTRACT FROM AUTHOR]

Large gas engines are typically applied to compensate for peak loads and grid instabilities in the electric power supply. A key component of these engines is the spark plug. Because of the harsh conditions encountered in their use, the spark plug electrodes are subject to significant wear. Conventional electrodes are expensive due to the precious metal alloys they contain. As an alternative, ceramic materials from the groups of silicide, carbides, and nitrides were selected for preliminary experiments that investigate functional as well as mechanical properties and wear behavior. Because of the harsh conditions during operation, the new materials must have a high melting temperature, good thermal shock resistance, high thermal conductivity, and high corrosion/oxidation resistance as well as high density. It was found that the mechanical and thermomechanical properties of certain ceramic candidates are sufficient for application as spark plug electrodes. Furthermore, the chosen ceramic materials achieve an adequate performance in terms of secondary voltage trace and ignition behavior. However, wear resistance may not be sufficient for service times longer than the service time of existing spark plugs and further research is still necessary before ceramic electrodes may be established as a commercial alternative to existing electrodes. [ABSTRACT FROM AUTHOR]

The thermal shock resistance of ceramics is a key factor for determining the durability of ceramic components under transient thermal conditions and is also one of the key factors for evaluating the stability of ceramics under extreme thermal conditions. After rapid heating or cooling, the surface and internal thermal stress mismatches of ceramics can cause severe thermal damage. Two main types of ceramic thermal shock exist: rapid cooling and rapid heating thermal shock. This article presents a broad understanding and insight into fundamental theory and experimental methods for ceramic thermal shock testing. The experimental equipment and procedures, test result evaluation, and material characterization of ceramic thermal shock are summarized. Moreover, outlooks and perspectives are discussed for testing and characterizing ceramic thermal shock resistance. This review will be helpful to researchers performing studies in the relevant fields of ceramics. [ABSTRACT FROM AUTHOR]

Silica gel‐modified hydratable magnesium carboxylate (HMC) is used as the binder for refractory castables. The mechanical strength and thermal shock resistance of HMC bonded and silica gel‐modified HMC‐bonded castables were compared. When the HMC/silica gel mass ratio is 2, the cold modulus of rupture, the hot modulus of rupture, the residual strength ratio after three‐times water quenching tests, and the matrix‐specific fracture energy of the castables were increased by 300%, 124%, 44.7%, and 132%, respectively, compared with HMC‐bonded castables. The characterization of microstructure evolution of silica gel‐modified HMC‐bonded castables indicated that a small amount of liquid phase generated is conducive to improving the high‐temperature mechanical properties. The in situ alumina‐rich spinel and needle‐like mullite toughened the matrix and enhanced the thermal shock resistance of the castables by "microcrack generation" and "preventing crack propagation" mechanisms. [ABSTRACT FROM AUTHOR]

This paper aims to improve the density and thermal shock resistance of Y2O3 ceramics for the preparation of ultra‐pure high‐temperature alloy crucible materials. The doping effect of MgF2 content on the densification behavior, physical properties, and thermal shock resistance of Y2O3 ceramics was systematically investigated in this paper. The results suggested that the presence of MgF2 greatly promoted the growth of Y2O3 grains and the transformation of the pore structure by liquid‐phase sintering. And the mechanical properties of the MgF2‐doped Y2O3 ceramics were significantly improved. Besides, the marked improvement in the thermal shock resistance of MgF2‐doped Y2O3 ceramics was attributed to the synergistic action resulting from the growth of grain size and the enhancement of the crack deflection effect. In particular, the relative density of Y2O3 ceramics doped with 1.5 wt% MgF2 reached 96.4% and the residual flexural strength ratio after thermal shock achieved 45.0%, showing an excellent application prospect. [ABSTRACT FROM AUTHOR]

Chromium–corundum, as a common refractory material, is broadly applied in high‐temperature kilns due to its superior thermal stability and high melting point. Unfortunately, this refractory is susceptible to corrosion and destruction under extreme furnace conditions by chemical erosion, mechanical wear, and thermal shock, which significantly shortens its useful life. Accordingly, in recent years, the issue of how to improve the slag corrosion resistance, mechanical, and sintering properties of chromium–corundum refractories has aroused widespread attention. In this work, the corrosion behavior and application status of chromium–corundum refractories in Ausmelt furnace, waste incinerator, coal water slurry gasifier, and HImelt melting reduction furnace are analyzed and discussed. To improve the service life of chromium–corundum refractories, the enhancement method and mechanism of sintering performance, mechanical properties, slag corrosion resistance, and thermal shock resistance are also summarized. Finally, some suggestions and prospects are made for the enhancement and longevity of chromium–corundum refractories. [ABSTRACT FROM AUTHOR]

Thermal shock behaviors of porous alumina samples with different porosities (4.6–16.0 %) and mean grain sizes (2.72–5.02 μm) were investigated under different quenching temperatures. The slit island method was used to analyze the structures of the pores. The effect of the pore structure on the thermal shock resistance of alumina ceramics was described quantitatively. The results revealed that the thermal shock resistance decreased when the fractal dimension of the pores increased. Alumina ceramic strips with a porosity and mean grain size of 4.6 % and 5.02 μm, respectively, were fabricated using raw powders with a mean particle size of ∼0.3 μm. These samples possessed the highest residual strength ratio (∼46.16 % at 600 °C) and critical temperature difference (∼262 °C). In addition, the fractal characterization of cracks on the surfaces of the alumina ceramics after thermal shock was carried out using the box-counting dimension method. In addition, we investigated the correlation between the mechanical properties and fractal dimensions of the surface cracks. The box-counting dimension increased with crack propagation and negatively correlated with the residual strength. Furthermore, the propagation rate of the surface cracks decreased as the temperature difference increased, resulting in a decrease in the growth rate of the fractal dimension. [ABSTRACT FROM AUTHOR]

Industrial boilers operate in extreme environments and are prone to degradation caused by high temperature oxidation, corrosion, and erosion. Protective coatings provide boiler components with protection to prolong their operation lifetime. Thus, a glass-ceramic coating has been developed using a slurry spray technique on carbon steel AS/NZS 3678 substrates. Microstructure, mechanical characteristics, and high temperature performance of the coating were investigated. The coating composed of chemically inert oxide ceramics dispersed in a glassy silicate binder matrix. The adhesion strength of the coating was 10.79 ± 0.86 MPa. Coating mass loss after abrasion test was 0.013 % of the tested specimen. The coating withstood at least 75 air quenched thermal shock cycles from 800 °C to the room temperature without any visible spallation and cracks. The coating mostly remained undamaged after cyclic oxidation at 800 °C for 10 cycles. However, minor iron oxide formation was observed, specifically, in relatively thin sections of the coating. The oxidation resistance of the boiler steel has been improved with the developed coating. The linear oxidation rate constant of the boiler steel has been statistically reduced from 6.90 × 10−4 mg cm−2 s−1 to 1.95 × 10−4 mg cm−2 s−1 for coated steel (p = 0.007). The developed slurry spray glass-ceramic coating is a potential candidate for boiler environments. [ABSTRACT FROM AUTHOR]

Excellent properties are required for refractories used for secondary refining because of the harsh service conditions. The current study investigated the effect of calcium boride (CaB 6) on the properties of magnesium oxide (MgO)‒based refractories. The sample with 0.4 wt% CaB 6 exhibited excellent properties. It possessed the highest bulk density indicating that a suitable content of CaB 6 can increase the compactness of the refractories. The in-situ formation of aluminum oxycarbonitride (Al 3 CON) at high temperatures in the MgO-based refractories was from the reaction of Al, Al 4 C 3 , AlN, and Al 2 O 3 due to the addition of Al powders, which endowed them with high strength. The refractory containing 0.4 wt% CaB 6 also exhibited the highest hot modulus of rupture (HMOR) of 26.6 MPa, which was around 2.5 times the strength of commercial MgO‒CaO bricks and 1.5 times that of the samples without CaB 6 addition. In addition, it exhibited the best oxidation resistance revealed by the minimum thickness of the decarbonization zone, because the addition of CaB 6 promoted the formation of a dense magnesium aluminate spinel (MgAl 2 O 4 , MA) layer between the oxidized and non-decarburized zone in the refractories, thereby promoting the resistance of the samples to oxidation. It also exhibited excellent thermal shock resistance, and the residual strength ratio reached 76.6 %. The corrosion depth of the sample containing 0.4 wt% CaB 6 was 9.8 % that of the MgO‒CaO bricks. This work indicates a potential alternative for producing high‒performance resin‒bonded MgO-based refractories with CaB 6 in secondary refining furnaces. [ABSTRACT FROM AUTHOR]

Zirconium carbide (ZrC) is considered to be a potential candidate for ultra high temperature applications due to its high melting point, good chemical inertness, and ablation resistance, but the monolithic form suffers from low fracture toughness and hence poor thermal shock resistance. Reinforcing it using continuous carbon fibers (Cf) to create an ultra high temperature ceramic matrix composite is an obvious solution, however densifying ZrC requires the use of very high temperatures combined with significant pressure, such as obtained by using hot pressing or spark plasma sintering, which risks damaging fibers. In the present work, radio frequency‐assisted chemical vapor infiltration (RF‐CVI) has been investigated with a view to forming Cf/ZrC composites. These initial experiments revealed the ability to deposit pure, nano‐grained, and near stoichiometric ZrC with deposition occurring preferentially from the center of the sample due to the nature of the inverse temperature profile developed. The deposited ZrC grains were in the range of 4–9 nm in size and had a lattice parameter of 0.4750 nm. The work also showed that the use of RF‐CVI enabled the minimization of early pore sealing, a common problem for conventional CVI. [ABSTRACT FROM AUTHOR]

Advances in vat photopolymerization 3D printing have the potential to significantly improve the production of ceramic materials for electrochemical energy devices. Solid oxide fuel cells (SOFCs) and solid oxide electrolysis cells (SOECs) necessitate high‐resolution ceramic manufacturing methods, as well as precisely controlled porosity (≈20–40%) for optimal gas transport. Achieving a balance between this porosity and mechanical integrity, especially under thermal stress, remains a challenge. Herein, the successful fabrication of porous yttria‐stabilized zirconia (YSZ) ceramics using vat photopolymerization 3D printing is demonstrated, achieving porosities ranging from 6% to 40% and corresponding grain sizes of ≈80–550 nm. It is found that 3D‐printed YSZ with ≈33% porosity exhibited a Weibull modulus of m = 5.3 and a characteristic strength of over 36 MPa. In the investigation, it is further revealed that these ceramics can withstand thermal shock up to 500 °C, retaining over 70% of their flexural strength. This remarkable performance suggests significant potential for 3D‐printed porous YSZ in SOFCs and SOECs, paving the way for potential improved efficiency, reduced fabrication costs, and innovative designs in these next‐generation clean energy technologies. [ABSTRACT FROM AUTHOR]

To clarify the mechanism of destructive knock combustion and piston ablation in heavy-duty diesel engines operating at low temperatures, CONVERGE simulation and wall temperature measurement were performed. The results show that as the initial temperature (intake valve closing instant) decreases from 380K to 307K, the spray wet-wall ratio increases from 12.8% to 22.2%. The fuel film evaporates slowly at low temperature before the hot flame, so the ignition is seriously delayed until the fuel injection ends, and the free-jet autoignition shifts to wall-attached combustion. However, the fuel film evaporation reverses after hot flame, and the maximum evaporation rate at 307K is about 54 times that at 380K. The wall temperature rises sharply to 350-450°C during wall-attached combustion. As the initial temperature decreases, the maximum pressure rise rate increases from 0.9MPa/°CA to 8.3MPa/°CA, and the pressure waves repeatedly oscillate along the end-center-end path in the cylinder. The highest pressure at the monitoring point is nearly an order of magnitude higher than the average, and the oscillation amplitude is as high as 6-10MPa, which far exceeds the failure threshold. The piston whose strength has been greatly reduced after thermal shock quickly undergoes ablation damage under strong pressure shock. [ABSTRACT FROM AUTHOR]

Enhancing the lifetime of perovskite solar cells (PSCs) is one of the essential challenges for their industrialization. Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions. However, the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging, respectively, resulting in irreversible damage to the morphology, component, and phase of stacked materials. Herein, the viscoelastic polymer polyvinyl butyral (PVB) material is designed onto the surface of perovskite films to form flexible interface encapsulation. After PVB interface encapsulation, the surface modulus of perovskite films decreases by nearly 50%, and the interface stress range under the dynamic temperature field (−40 to 85 °C) drops from −42.5 to 64.8 MPa to −14.8 to 5.0 MPa. Besides, PVB forms chemical interactions with FA+ cations and Pb2+, and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film. As a result, the optimized device's efficiency increases from 22.21% to 23.11%. Additionally, after 1500 h of thermal treatment (85 °C), 1000 h of damp heat test (85 °C & 85% RH), and 250 cycles of thermal cycling test (−40 to 85 °C), the devices maintain 92.6%, 85.8%, and 96.1% of their initial efficiencies, respectively. [ABSTRACT FROM AUTHOR]

Thermal shock resistance and mechanical reliability of aluminum nitride (AlN) ceramic substrates are essential in electronic device modules. In this study, the thermal shock behavior of AlN doped with aluminum - yttrium oxide (Al - Y 2 O 3) was explored. The results indicate that adding Al to AlN ceramics increases its flexural strength, thermal conductivity, and thermal expansion coefficient. The microcracks caused by thermal mismatch between the AlN matrix and the secondary phases relieved internal stress, thereby improving thermal shock resistance of AlN ceramics. Furthermore, the addition of Al isolates and homogenizes the secondary phases, resulting in a more uniform microstructure and strengthened grain boundaries, which enhance the flexural strength, Weibull modulus, and thermal shock resistance. After introducing 0.5 wt% Al, the Weibull modulus of AlN ceramics increased by 73.37 %, and their critical thermal shock temperature difference exceeded 800 °C, with a maximum residual strength of 488.01 ± 48.26 MPa at 600 °C. Overall, an appropriate amount of Al improves the reliability and thermal shock resistance of AlN ceramics. [ABSTRACT FROM AUTHOR]

Conventional aluminum nitride (AlN) ceramics exhibited insufficient mechanical properties expected from their potential applications in the presence of dynamic loads and intensive stresses caused by thermal shock. In this study, the mechanical properties of AlN ceramics were enhanced by toughening them using AlN whiskers (AlNw) via gel casting followed by low‐temperature sintering at 1650°C. The addition of AlNw simultaneously increased the bending strength, toughness and thermal conductivity of the AlN ceramics. The maximum values of the bending strength, toughness, and thermal conductivity of 9.0 wt% AlNw/AlN were 303.92 MPa, 3.92 MPa·m1/2 and 186.53 W·m−1·K−1, respectively, which were higher than those of the AlN ceramics by 39.93%, 61.31% and, 15.61%, respectively. The AlNw in AlNw/AlN ceramics tightly bonded with the ceramic matrix, leading to two characteristic toughening mechanisms in the ceramics: crack pinning and deflection at irregular grain boundaries caused by doped whiskers, as well as bridging and stress relaxation caused by whiskers incorporated with the grains. Moreover, the one‐dimensional morphology of AlNw can provide a channel for quick photon transport, thereby enhancing the thermal conductivity of AlNw/AlN. [ABSTRACT FROM AUTHOR]

Selective laser flash sintering utilizes a scanning laser as a heat source to locally initiate flash sintering in the regions scanned by the laser. A key challenge towards utilizing this process for additive manufacturing (AM) is the induced electrical current that arises during flash sintering. With traditional scan patterns conducted with static electric fields, electrical and thermal runaway and associated thermal shock cracking occur. In this study, several open‐loop control strategies with static and dynamic applied electric fields were utilized to control peak currents. These strategies were shown to be effective in reducing peak currents to below 1.0 µA and reducing the severity of, but not completely eliminating cracking. Alternative strategies are suggested that could lead to complete elimination of cracks. [ABSTRACT FROM AUTHOR]

Hierarchical design was applied to core-shell B 2 O 3 @SiO 2 microcapsule, followed by fabrication of the SiC–B 2 O 3 @SiO 2 coating by a combination of entrapping and hot dip processes. Among the C/C-SiC-BS2, C/C-SiC-BS4 and C/C-SiC-BS6 samples, the C/C-SiC-BS4 composite exhibits long-term antioxidant capabilities, with only a 2.30 % mass loss as oxidized at 973 K for 1500 h, and 2.35 % at 1073 K for 2600 h. Furthermore, after enduring 150 thermal shocks between 293 K and 1173 K, its mass loss is only 2.07 %. The XRD patterns detected the existence of B 2 O 3 and SiO 2 phases, and the SEM and EDS analysis proved the borosilicate glass, indicating the excellent performances came from the synergistic self-healing effects of the B 2 O 3 , SiO 2 phases, and borosilicate glass. Thus, within the temperature ranges from 873 K to 1273 K, the oxygen penetration shifts from osmotic state to defect diffusion in coating. This research emphasizes the significance of hierarchical designs for core-shell sacrificial phase in silicate coatings, thereby enhancing their long-term applicability. • Hierarchical design was applied to the B 2 O 3 @SiO 2 microcapsule by a simple sol-gel technique. • Core-shell microcapsule successively activated the SiO 2 , B 2 O 3 phases and borosilicate glass in self-healing. • The composite yielded excellent combinations of long-term antioxidant and thermal shock resistances. • This study highlights the hierarchical designs for core-shell sacrificial phase in silicate coatings. [ABSTRACT FROM AUTHOR]

The durability of thermal barrier coatings (TBCs) is significantly influenced both by the ceramic top coat and the bond coat. In this study, novel YbGdZrO ceramic coats were deposited on the surfaces of three types of Cr-modified (Ni, Pt)Al bond coats via electron beam physical vapor deposition (EB-PVD) technique. These Cr-modified (Ni, Pt)Al bond coats were fabricated by magnetic sputtering Cr onto the (Ni, Pt)Al bond coats with varying sputtering times of 30, 60, and 90 min. The results indicates that the thickness of the Cr-modified layer increases with the extension of sputtering time. A short deposition time of 30 min is adequate for achieving an appropriate Cr content in the (Ni, Pt)Al bond coats, which ensures selective oxidation of Al element within the bond coat and further enhances the metallurgical interfacial bonding strength with the ceramic coat by adapting to the concentration gradient diffusion. However, as the sputtering time is extended to 60 and 90 min, α-Cr begins to form in the Cr-modified (Ni, Pt)Al bond coats, which negatively affects the oxidation resistance of the bond coat. Consequently, the thermal shock life of the TBCs samples is significantly reduced with increasing sputtering time. The longest thermal shock lifetime is obtained on the bond coat with Cr plating time of 30 min owing to a differing thermally grown oxide formation and failure mechanism. [ABSTRACT FROM AUTHOR]

Ceramic industry consumes large amounts of raw materials, including costly and environmental impact iron based-pigments. Steel rolling (SR) and wire drawing (WD) waste, rich in iron (>67 wt %), present a viable alternative. This study aims to develop high value stoneware pastes for tableware products by substituting commercial pigments with SR and WD. The influence of incorporation content (3, 5 and 10 wt %) and pre-treatments (sieving at 250, 150 and 63 μm, and grinding followed by sieving at 63 μm) on the samples properties was assessed including weight loss, firing shrinkage, apparent density, flexural resistance, and water absorption. The laboratory scale results revealed that darker hues, ranging from grey to reddish, were obtained when SR and WD were incorporated in the stoneware paste (beige colour). The smaller the particle size, more homogeneous is the developed colour, which is intensified as higher is the incorporation level. The prototypes (plates) were characterized in terms of thermal shock, edge impact, cracking and microwaves resistance, water absorption, and leaching behaviour, demonstrating that they met the industrial requirements. Thermal shock resistance was enhanced and the levels of leached Fe, Pb, Cd, Ni, Cr, Mo, V, Zn, and Cu, were below permissible limits (EU Ceramic Directive 84/500/EEC, Decree-Law n°152/2017, Decree-Law n°236/98 and WHO Guidelines for Drinking-Water Quality) confirming their effective immobilization. Concluding, this work shows the viability of using mill scale waste as a valuable secondary raw material in stoneware pastes acting as a chromophore agent. Dark colours are obtained while preserving the product technical characteristics, promoting sustainable production and reducing landfilled waste. [ABSTRACT FROM AUTHOR]

This study aims to advance the application of magnesia-zirconia (MgO–ZrO 2) refractories in non-ferrous metal smelting furnaces by enhancing their thermal shock resistance. To fabricate MgO–ZrO 2 –MgAl 2 O 4 refractories, tabular corundum particles and activated α-Al 2 O 3 powder are integrated into MgO–ZrO 2 refractories. The analysis of thermal shock resistance, phase composition, and microstructure of the samples was conducted to gain insights into the toughening mechanisms. The results reveal a substantial enhancement in thermal shock resistance with the addition of 15 wt% tabular corundum (1–0.5 mm) and activated α-Al 2 O 3. Compared to samples without these additives, a notable increase of over 50.0 % in the ratio of residual cold modulus of rupture is shown. The enhancement in thermal shock resistance is primarily attributed to the in-situ generated MgAl 2 O 4 spinel. This process involves volume expansion and increased thermal expansion mismatch, which induce microcrack toughening. Additionally, larger tabular corundum particles form in-situ MgAl 2 O 4 spinel, causing crack deflection and branching, thus extending the crack propagation pathway. Furthermore, the presence of micropores in the spinel zone absorbs the energy required for crack propagation, thereby improving toughness and thermal shock resistance. Consequently, the MgO–ZrO 2 –MgAl 2 O 4 refractories containing in-situ MgAl 2 O 4 spinel with micropores are promising candidate for chrome-free refractories used in non-ferrous metal smelting furnaces. [ABSTRACT FROM AUTHOR]

Based on the ultrasonic welding technology, this study uses three different welding widths to weld copper cables with different specifications. The influence of welding width on the mechanical properties and microstructure of each group of welded joints was systematically studied for the first time. The thermal shock test was carried out for each group of welded joints under optimum welding width to simulate the influence of severe temperature change environment on joint performance. It is found that the cross-sectional area of joint is 20 mm2 and optimal welding width of joint composed of two and three cables is 7 mm. The optimal welding temperature of the joint composed of four cables is 5 mm. Under the optimal welding width, the average shear strength of two-cable joint reaches 309.4 N. The four-cable joint is only 232.2 N. Moreover, the welding strength weakens significantly as the number of cables and the peak temperature decreases. The high temperature of bonding interface is the key factor to form a good weld. The peak temperature during welding is negatively correlated with the porosity of joint and positively correlated with peeling strength of joint. In addition, the morphology of ultrasonically welded joints has changed obviously after thermal shock test. With the participation of oxygen, the surface of welded joint is gray and bright brass, while the interior of joint is purple due to lack of oxygen. Moreover, the phenomenon of atomic diffusion and thermal expansion generates joints which were initially in a mechanically interlocked form and welding interface of the metallurgical bond under the action of high temperature. So the maximum joint peel strength is slightly improved. [ABSTRACT FROM AUTHOR]

In this study, 20 different types of magmatic-origin natural stones commonly used in the construction sector were subjected to the most prevalent aging effects in nature, namely freeze-thaw and thermal shock. Prior to and after the aging tests, the Solar Reflectance Index (SRI) values of each sample were calculated by measuring their solar light reflectance values and solar light scattering values. Additionally, the surface color measurements of each sample were taken according to the CIA color index, and the color change (∆E) values were calculated. The primary objective of this study is to determine the changes in SRI and ΔE values of natural stones due to freeze-thaw and thermal shock aging and to examine the impact of the findings on the formation of urban heat islands. As a result of the study, it was determined that the SRI values of the samples were higher after both aging experiments compared to before the aging experiments. When examining ΔE values, it was found that thermal shock experiments caused more significant color changes compared to freeze-thaw experiments. It has been determined that the overall increase in both SRI and ΔE values will contribute to the reduction of the urban heat island effect. [ABSTRACT FROM AUTHOR]

A new PD-FEM (peridynamics-finite element method) hybrid model method was proposed for solving thermal-mechanical coupling problems. Its solution region was divided into peridynamics and finite element subregions. The hybrid bonds introduced to mixed these two subregions were composed of finite element nodes and peridynamics material points. The hybrid model was used to simulate damage behavior of alumina ceramic plates under thermal shock loads. Calculation results showed that the cracks initiation and propagation obtained by the hybrid model were in good agreement with experiment results, which validated the accuracy and availability of the hybrid model. The PD-FEM hybrid model inherits the advantage of peridynamics in dealing with discontinuous problems. Because the finite element method is introduced, the model significantly improves the efficiency of studying thermal-mechanical coupling problems using peridynamics method. [ABSTRACT FROM AUTHOR]

This study investigates the impact of kaolin and boehmite alumina binders on the synthesis, catalytic properties, and attrition resistance of a La0.7Sr0.3FeO3 (LSF) perovskite catalyst designed for the chemical looping partial oxidation (CLPO) of methane to produce synthesis gas sustainably. The as-synthesized and used catalysts with varying kaolin and boehmite alumina contents (KB(x,y)/LSF) were scrutinized by a variety of characterization methods, including XRD, FE-SEM/EDS, BET, TPD-NH3, and TPD-O2 techniques. The catalytic activity of the synthesized samples was tested at 800 to 900 °C in a fixed-bed reactor producing syngas through the CLPO process over the consecutive redox cycles. Additionally, the attrition resistance of the fresh and used catalyst samples was examined in a jet cup apparatus to assess their durability against the stresses induced by thermal shocks or changes in the crystal lattice caused by chemical reactions. The characterization results showed the pure perovskite crystal structure of KB(x,y)/LSF catalysts demonstrating adequate oxygen adsorption capacity, effective coke mitigation capability, robust thermal stability, and resilience to agglomeration during repetitive redox cycles. Among the tested catalysts, KB(25,15)/LSF was identified as the superior sample, as it could consistently produce syngas with a suitable H2:CO molar ratio varying from 2 to 3 within ten redox cycles at 900 °C, with CH4 conversion and CO selectivity values up to 64% and 87%, respectively. The synthesized catalysts demonstrated a logarithmic attrition pattern in the jet cup tests at room temperature, featuring high attrition resistance after the erosion of particle shape irregularities or weakly bound particles. Moreover, the KB(25,15)/LSF catalyst used at 900 °C showed great resistance in the attrition test, warranting its endurance in the face of extraordinarily harsh conditions in fluidized bed reactors employed for the CLPO process. [ABSTRACT FROM AUTHOR]

This work is an attempt to develop a simple and accurate finite element formulation based on first-order shear deformation theory (FSDT) for the transient thermal stress analysis of a pre-twisted and tapered thin rotating functionally graded material (FGM) blade, induced due to the thermal shock. The neutral surface of the FGM blade is taken as the reference plane and the exact shear correction factor is obtained from the equivalent energy principle. The temperature-dependent material property at a point in the thickness direction is estimated according to the rule of mixture (ROM) and the Local representative volume elements (LRVE) homogenization model. A finite element formulation using FSDT in conjunction with the eight-noded isoparametric element, taking five degrees of freedom is developed. The top layer of the thin FGM blade is subjected to a thermal shock and the bottom layer is kept at the ambient temperature. The governing equation for the present formulation is obtained using Hamilton's principle. The accuracy of the present finite element formulation is established by comparing the results with the benchmark results. The parametric studies are conducted to investigate the effect of the angle of twist, variable chord and span, rotational speed, and accurate shear correction factor on the transient thermal stresses due to the thermal shock. Notably, there can be significant differences in the transient thermal stresses calculated by the two homogenization models viz., ROM and LRVE. Also, it is important to consider the exact shear correction factor in the formulation. [ABSTRACT FROM AUTHOR]

Mullite–cordierite saggar materials commonly used in the industry are easily corroded by LiNixCoyMn1−x–yO2 (LNCM) materials during the synthesis of Li‐ion batteries. To extend their service life, the influence of varying the proportion of calcium hexaluminate (CA6) ranging from 0 to 12 wt% on the sintering behavior of the mullite–cordierite system was investigated. These samples were then tested to evaluate their physical characteristics, resistance to corrosion by LNCM materials, and thermal shock stability. The experimental results show that the open‐pore structure formed by the interstacking grains of CA6 effectively impedes further penetration of the corrosion phase. Moreover, the addition of CA6 resulted in the in situ formation of anorthite within the material, enhancing its sintering and bonding properties and significantly improving the material's corrosion resistance. Consequently, incorporating CA6 effectively enhances the saggar's thermal shock stability and corrosion resistance. [ABSTRACT FROM AUTHOR]

This study investigates the dynamic response of an infinite structure comprising two coaxial cylinders employing the one-relaxation-time generalized thermoelastic diffusion model. The inner cylinder, serving as a cavity, possessing a radius a, while the outer cylinder has radius b. The inner cylinder is insulated and experiencing a localized thermal load with thickness 2 h. The outer cylinder, with radius b, is also experiencing to a localized thermal load with width 2 h, and its surface exhibits no traction. Additionally, the structure experiences the influence of a solenoidal body force. The analysis of this problem employs a combination of Laplace transform, inverse Laplace transform, and exponential Fourier transform techniques. Numerical analysis of the resulting solutions reveals the variations in temperature, displacement, radial stress, concentration, and potential fields as a function of the radial coordinate. Results indicate a minimal impact of the time interval on the temperature distribution, while displacement and radial stress exhibit significant time-dependent behavior. These findings highlight the significance of incorporating thermoelastic diffusion theory in the analysis of real-world engineering problems. [ABSTRACT FROM AUTHOR]

This document presents a program developed by Amin Houari from the University of Boumerdes for predicting damage in notched functionally graded materials (FGMs) plates using the extended finite element method (XFEM). The program is written in the USDFLD subroutine and includes variables and dimensions. It reads the X coordinate and assigns it to the first field variable. The program provides a computational simulation for analyzing the behavior of FGMs and predicting damage in notched structures. [Extracted from the article]

An experimental programme was designed to test 24 square columns (200 mm side and 1000 mm length) with different numbers of layers (one, two, three, four and five) of auxetic steel wire mesh (ASWM) as a substitute for stirrup reinforcement within the middle region of the column height. The effect of thermal shock was also assessed, with the tested columns divided into two sets of 12 damaged specimens and 12 undamaged specimens. Sufficient ties were provided at the column ends to prevent premature failure. The ASWM layers provided the columns with the required lateral confinement depending on the number of applied layers (NASWM) and the concrete compressive strength. Thermal shock was found to reduce the concrete compressive strength, thus degrading the column's performance in terms of ductility, strength and stiffness. The number of ASWM layers used significantly improved the ductility, energy absorption, and column axial capacity, but this improvement was limited to NASWM = 4 or 5, while the stiffness increased for all values of NASWM. The average enhancement in the column's axial capacity was 15% for the intact specimens, but this was reduced to approximately 10% under the effect of thermal shock. [ABSTRACT FROM AUTHOR]

In this work, we presented a model which consists of three layers with different materials; the second layer was taken to be viscous-elastic material, while the first and third layers are made of elastic material. This model is solved in the context of the generalized thermoelasticity theory with one relaxation time. The first layer's upper surface is taken to be traction-free and is subjected to a constant thermal shock. Nobody forces or heat sources affecting the layer. Laplace transform techniques are used. The solution in the transformed domain is obtained by using a direct approach. The inverse Laplace transforms are obtained using a numerical method based on the Fourier expansion technique. The effect of thermal shock is discussed and studied of the three layers on the behavior of the solutions, in the presence of viscoelastic effects and its absence. Numerical results are computed and represented graphically for the temperature, displacement, and stress distributions. [ABSTRACT FROM AUTHOR]

A large part of the cost of steel production in the world is related to the consumption of graphite electrodes. Electrode is the only material that maintains its electrical conductivity at high temperatures, and hence it is used as a conductor of electric current in EAF furnaces. Considering the high costs of graphite electrodes, any action that leads to reducing the consumption of graphite electrode can lead to increasing the productivity of steelmaking operations. In this study and as its novelty, the electrophoretic method was used to generate a ceramic coating for the protection of graphite electrodes. Electrophoretic deposition (EPD) is a two-step process in which charged particles suspended in a suspension move towards the oppositely charged electrode under the influence of an electric field which combine as a dense film on the surface. In the EPD technique, the particle size limit is not very important if a stable suspension is formed and micro and nano-sized particles can be used in this method. The numerical simulation of the thermal contour on the graphite electrode was done in ABAQUS software. Moreover, the surface morphology of graphite samples has been investigated via scanning electron microscopy (SEM). The created coating was a combination of Al2O3 and SiO2, which was placed on the surface of test samples by EPD treatment. The obtained results have the properties of resistance to thermal shock and show the increase in the life of coated graphite samples at different temperatures and times. [ABSTRACT FROM AUTHOR]